.center{
    width: 775px;
    height: 520px;
    margin-left:-30px;
    border-radius: 5px;
    margin-top: 3px;
}
.tezx{
    width: 100%;
    height: 350px;
    margin-top: 170px;
    background:url('../assets/zx.png');
    background-size:100% 100%;
    background-repeat:no-repeat;
    cursor: pointer;
}